feat: add PingAPI to check status of OSS and Cloud instance

[bednar]

Proposed Changes

1. Added PingAPI to check status of OSS and Cloud instance
2. Added an example how to use PingAPI
3. Added swift 5.5 to CI

Checklist

• CHANGELOG.md updated
• Rebased/mergeable
• A test has been added if appropriate
• swift test completes successfully
• Commit messages are in semantic format
• Sign CLA (if not already signed)

[codecov-commenter]

Codecov Report

Merging #39 (211c347) into master (2d21cfd) will increase coverage by 35.24%.
The diff coverage is 0.00%.

@@             Coverage Diff             @@
##           master      #39       +/-   ##
===========================================
+ Coverage   52.02%   87.27%   +35.24%     
===========================================
  Files         135       10      -125     
  Lines        6199      707     -5492     
===========================================
- Hits         3225      617     -2608     
+ Misses       2974       90     -2884     

Impacted Files	Coverage Δ
Sources/InfluxDBSwiftApis/InfluxDB2API.swift	95.45% <0.00%> (-4.55%)	⬇️
Tests/InfluxDBSwiftApisTests/SecretsAPITests.swift
...rces/InfluxDBSwiftApis/Generated/Models/DBRP.swift
...rces/InfluxDBSwiftApis/Generated/Models/Task.swift
...ces/InfluxDBSwiftApis/Generated/Models/Ready.swift
...nfluxDBSwiftApis/Generated/Models/DBRPCreate.swift
.../Generated/Models/AuthorizationUpdateRequest.swift
...SwiftApis/Generated/Models/TaskCreateRequest.swift
...ces/InfluxDBSwiftApis/Generated/Models/Users.swift
...enerated/Models/AddResourceMemberRequestBody.swift
... and 116 more

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